Journal article
Weak selection and recent mutational changes influence polymorphic synonymous mutations in humans
Proceedings of the National Academy of Sciences - PNAS, Vol.103(18), pp.6940-6945
05/02/2006
DOI: 10.1073/pnas.0510638103
PMCID: PMC1458998
PMID: 16632609
Abstract
Recent large-scale genomic and evolutionary studies have revealed the small but detectable signature of weak selection on synonymous mutations during mammalian evolution, likely acting at the level of translational efficacy (i.e., translational selection). To investigate whether weak selection, and translational selection in particular, plays any role in shaping the fate of synonymous mutations that are present today in human populations, we studied genetic variation at the polymorphic level and patterns of evolution in the human lineage after human-chimpanzee separation. We find evidence that neutral mechanisms are influencing the frequency of polymorphic mutations in humans. Our results suggest a recent increase in mutational tendencies toward AT, observed in all isochores, that is responsible for AT mutations segregating at lower frequencies than GC mutations. In all, however, changes in mutational tendencies and other neutral scenarios are not sufficient to explain a difference between synonymous and noncoding mutations or a difference between synonymous mutations potentially advantageous or deleterious under a translational selection model. Furthermore, several estimates of selection intensity on synonymous mutations all suggest a detectable influence of weak selection acting at the level of translational selection. Thus, random genetic drift, recent changes in mutational tendencies, and weak selection influence the fate of synonymous mutations that are present today as polymorphisms. All of these features, neutral and selective, should be taken into account in evolutionary analyses that often assume constancy of mutational tendencies and complete neutrality of synonymous mutations.
Details
- Title: Subtitle
- Weak selection and recent mutational changes influence polymorphic synonymous mutations in humans
- Creators
- Josep M Comeron - Department of Biological Sciences, University of Iowa, 212 Biology Building, Iowa City, IA 52242, USA. josep-comeron@uiowa.edu
- Resource Type
- Journal article
- Publication Details
- Proceedings of the National Academy of Sciences - PNAS, Vol.103(18), pp.6940-6945
- DOI
- 10.1073/pnas.0510638103
- PMID
- 16632609
- PMCID
- PMC1458998
- NLM abbreviation
- Proc Natl Acad Sci U S A
- ISSN
- 0027-8424
- eISSN
- 1091-6490
- Publisher
- United States
- Language
- English
- Date published
- 05/02/2006
- Academic Unit
- Biology
- Record Identifier
- 9983991998102771
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